Electric switch



C. HATAY ELECTRIC SWITCH Aug. 28, 1934.

Filed April 25, 1932 ..lnIlILiI!i|\l!.wllnuiir liiiiiiiil.,liiiiiiiiiii: III! 7 mvsmofag J WW ATTORNEY Patented Aug. 28, 1934 PATENT- OFFICE.

ELECTRIC SWITCH Charles Hatay, Berlin-Charlottenburg, Germany,

assignor to General Electric Company, a corporation of New York Application April 26, 1932, Serial No. 607,645 In Germany April 29, 1931 6 Claims.

The present invention relates to electric switches generally and more particularly the invention relates to switches of the liquid fiow type in which the movements of a magnetizable body are availed of to make and break the electrical contact between the electrodes in said device.

In my co-pending application, Serial Number 481,049 filed September 10, 1930 which became Patent No. 1,935,710 on November 21, 1933, a switch of the above type is disclosed in which the magnetizable body is attached to a hollow plunger of insulation material, said plunger being filled or partially filled with mercury. The electrodes of the switch are rod shaped, one being immersed in the mercury in the plunger at all positions of said plunger and the other being immersed in the mercury in the container of the device. The make and break of electrical con tact between said electrode is effected by the successive movements of said plunger uniting and separating the mercury pool in the container and the mercury pool in the plunger of the device.

The object of the present invention is to provide a. better electrical contact between the electrode and the mercury in the plunger. Another object of the invention is to reduce the strain on the parts of such switches during the operation and transportation thereof. A further object of the invention is to protect the container of the device from the spark resulting from the make and break of electrical contact between the, electrodes. A further object of the invention is to prolong the useful life of magnetically operated mercury switches. Still further objects and advantages attaching to the device and to its use and operation will be apparent to those skilled in the art from the following particular description and from the appended claims.

The invention attains its objects by increasing the contact area between the electrode and the mercury in the plunger, by providing springs to control the vertical movements of the plunger in the container during the operation and transportation of the device, and by arranging a wall of the plunger between the locus of the spark and the container. Accordingly the insulation part of the plunger is a straight-sided trough of annular shape the side of greater diameter being of greater length and the electrode is forked, carrying a ring at its lower end which is concentric with the annular insulation part of the plunger. The ring part of the electrode is immersed in the mercury in the insulation part of the plunger at all operating positions of said plunger. The core part of the plunger is attached to the insulation part thereof in such manner that said core is out of the mercury in said container at all operating positions of said plunger. A spring is attached to the external side of the bottom part of said plunger to act as a buffer between said plunger and that part of container against which it rests during the operation of the device or during the transportation thereof and another spring presses against the bottom of the electrode and the internal side of said plunger, both of said springs co-operating to lessen the strain on the container of the device by controlling the vertical movements of said plunger in said container.

In the. drawing accompanying and forming part of this specification an embodiment of my invention is shown in which Fig. 1 is a side elevational view, partly in section, of my new and novel magnetic switch in a closed circuit position.

Fig. 2 is a similar view of the switch in an open circuit position and rotated on its vertical .axis.

Fig. 3, is a side elevational view of the'new and novel core member of the switch and Fig. 4 is a perspective view of one of the electrodes of the switch.

Referring to Figs. 1 and 2 of the drawing the switch comprises a glass container 1 having a plunger 3, 4 therein, electrodes 8 and 12 sealed therein at each end thereof, and a body of mercury therein. The insulation part of said plunger 3, 4, which is, for example, of quartz, is a straightsided trough of annular shape, the side 4" of greater diameter is considerably greater in length than the side 4' thereof. The magnetizable part 3 of said plunger 3, 4 is a core for the magnet coil 2 surrounding said container I. Said part 3 is fitted to the outer wall of side 4 to support insulation part 4 by friction and by prongs 3 (Fig. 3). Saidpart 3 is out of the mercury in said container 1 at all operating positions of said plunger 3, 4, as shown in Figs. 1 and 2, thus said mercury is not heated by the electric field created about said part 3 during the energizing of said coil 2. Slits 3" are provided in said part 3 to reduce the eddy currents generated thereat by said coil 2 and thus to prevent heating of the switch.

Electrode 8, shown in detail in Fig. 4, consists of two prong members 6 and 6" extending from a ring-shaped part 7, their bent parts 6 are butt welded to each other and stud welded to electrode 8 to simplify the manufacture thereof and to readily transmit electrical energy. The median line of the ring-shaped part 7 coincides with the median line of the sides 4' and 4" of the plunger 3, 4 and said ring 7 is located in the space between said part 4' and said part 4" and in such posipresses against said electrode part7 and the bdttom of plunger part 4, said spring 10 having sufficient strength to counter-act the buoyancy of. part 4 in the mercury to maintain said plunger 3, 4 in its contact making position in said container 1 as shown in Fig. 1. Springs 9 and 10 cooperate to prevent the free vertical movements of said plunger 3, 4 in said container 1 and thus prevent strain on said container 1 during transportation and operation of the device. The lateral movements of plunger 3, 4 in said container 1 are controlled by protuberances on said electrode parts 6 and 6" and by protuberances on core 3 and prongs 3', as illustrated in Figs. 1 and 2.

When coil 2 is energized core 3 is attracted upward to the center of said coil 2, spring 10 is compressed and plunger 3, 4 is thus moved upward a sumcient distance to separate the mercury in the plunger 3, 4 from that in container 1 which breaks the electrical connection between said electrodes 8 and 12 to interrupt current flow through thedevice'as shown in Fig. 2. On the de-energizing of coil 2 plunger 3, 4 is forced back to its contact making position by spring 10, spring 9 acting as a buffer between part 4 and container 1 to reduce the strain on said parts. The separation and uniting of the mercury and thus the spark resulting from the make and break of the electrical contact between said electrodes 8 and 12 takes place at the rim of side 4' of the trough 4 and the walls of container 1 are protected from the effects of said spark by side 4" by virtue the enclosing structure heretofore described.

While I have shown anddescribed and have pointed out in the annexed claims certain new and novel features of the invention it will be understood that various omissions, substitutions and changes in the forms and. details thereof may be made by those skilled in the art without departing from the broad spirit and scope of the invention for example, the switch is a gas filled switch or a vacuum switch as desired.

' What I claim as new and desire to secure by Letters Patent of the United States is:

1. A switch comprising a container, electrodes sealed therein, a body of mercury therein, a plunger in said container, said plunger having acore and "being adapted on successive movements thereof to make and break the electrical contact between said electrodes and a spring between, and pressing against one of said electrodes and said plunger and a spring between said plunger in said container during the operation and transportation of the device.

2. A switch comprising a container, electrodes sealed therein, a body of mercury therein, a hollow plunger in said container, one of said electrodes having an' annular shaped -part, said plunger having a core and being adapted on successive movements thereof to make and break the electrical contact between said electrodes, a spring between, and pressing against, the annular shaped electrode part and said plunger and a spring between said plunger and said container, both said springs cooperating to control the vertical movements of said plunger in said container during the operation and transportation of the device.

3. A switch comprising a container, electrodes sealed therein, a body of mercury therein, a plunger in said container, said plunger having a slitted core out of the mercury in said container at all operating positions of said plunger and adapted on successive movements thereof to make and break the electrical contact between said electrodes.

4. A switch comprising a container, electrodes sealed therein, a body of mercury therein, a

at all operating positions of said plunger, said plunger being adapted on successive movements thereof to make and break the electrical contact between said electrodes.

5. A switch comprising a container, electrodes sealed therein at each end thereof, a body of mercury therein, a plunger in said container, said plunger being an annular shaped trough of insulation material, the side of greater diameter being greater in length than the other side thereof, and a core mounted on said trough, said core being out of the mercury in said container at all operating positions of said plunger, one of said electrodes being immersed in the mercury in said trough at all operating positions of said plunger. 6. A switch comprising a container, electrodes sealed therein at each end thereof, a body of mercury therein, a plunger in said container, said plunger being an annular shaped trough of insulation material, the side of greater diameter being greater in length than the other side thereof,

and a core mounted on the side of greaterv length 'of said trough, one of said electrodes being im- CHARLES HATAY. 

